1. Field of the Invention
The invention relates to a belt member, and relates also to a seatbelt apparatus of a vehicle seat, the seatbelt apparatus including the belt member.
2. Description of Related Art
For example, Japanese Patent Application Publication No. 2012-240432 (JP 2012-240432 A) describes a seatbelt apparatus used to protect an occupant seated in a vehicle seat. This seatbelt apparatus includes a wider seatbelt to reduce a contact pressure of the seatbelt per unit area, thereby attenuating an impact that is applied from the seatbelt to an occupant. In the seatbelt apparatus described in JP 2012-240432 A, a guide member disposed at the rear of a shoulder of an occupant guides the seatbelt toward a retracting device. The guide face of the guide member, on which the seatbelt is guided, is formed such that curved guide portions, each having a C-shaped cross-section, are disposed so as to face each other. The curved guide portions are configured to curve and fold back the opposite end portions of the seatbelt in its width direction. The distance between the curved guide portions in the width direction is gradually reduced in a direction in which the seatbelt is retracted into an accommodating device.
In the seatbelt apparatus described in JP 2012-240432 A, when the seatbelt is retracted, the width of the seatbelt is reduced when the seatbelt is guided by the curved guide portions of the guide member, each having a C-shaped cross-section. Further, when the seatbelt is retracted, after the seatbelt passes through the guide member and is then pulled out of the guide member, the width of the seatbelt is increased due to the restoring force of the seatbelt itself. Thus, if the distance between the guide member and the accommodating device (retracting device) is set long, after the width of the seatbelt is once reduced by the guide member, the width of the seatbelt is expected to be increased due to the restoring force of the seatbelt itself, at a position between the guide member and the accommodating device. In this case, the seatbelt of which the width has been increased attempts to be retracted into the retracting device, causing a possibility that the seatbelt will fail to be smoothly retracted into the retracting device.